ABSTRACT
The fresh leaves of Mentha piperita L. (Lamiaceae) were collected, and after proper shade drying, the essential oil was extracted through hydro- distillation using Clevenger’s apparatus. The gas chromatography-mass spectroscopy (GC-MS) analysis of the oil showed that menthol (37.20%) and menthone (22.52%) were the major active constituents. In the present work, its antibacterial efficacy was screened with the disc diffusion method, where the maximum zone of inhibition was found against Salmonella typhi (17 ± 0.1 mm) Further, the in vitro efficacy of oil was validated against bacterial pathogens such as Escherichia coli (ATCC 25922), Proteus vulgaris (MTCC 1771), Salmonella typhi (MTCC 733), Klebsiella pneumoniae (MTCC 109), and Pseudomonas aeruginosa (MTCC 103) by using the broth microdilution method (CLSI). The minimum inhibitory concentration (MIC) was recorded as 0.83 mg/mL, 1.19 mg/mL, 0.30 mg/mL, 0.61 mg/mL, and 1.09 mg/mL, respectively. Furthermore, the oil showed toxicity against heavy inoculum density, quick killing activity, broad antimicrobial spectrum, thermostability, and long shelf-life. The in vivo investigations of its active constituents will be needed to perform in order to confirm the mechanism of action for curing human diseases.
